/* Populations */

/*
 *Initial Population
 */

define "Initial Population":
  true

/*
@dataElement: HIV.A.DE18 - Gender
@activity: HIV.A6.1 Review sociodemographic data with client | HIV.A5 Create new client record
@description: Gender of the client
*/

/*
 * By Administrative Gender of Patient Stratifier
 * Need to expand codes
 */

define "By Administrative Gender Stratifier":
  case 
      when Patient.gender = 'male' then Concepts."Male"
      when Patient.gender = 'female' then Concepts."Female"
      when Patient.gender = 'transgender female' then Concepts."Transgender female"
      when Patient.gender = 'transgender male' then Concepts."Transgender male"
      else Concepts."Other - HIV.A.DE23"
  end

/* End of Visit date A.DE3 */

/*
@dataElement: HIV.A.DE17 - Age
@activity: HIV.A6.1 Review sociodemographic data with client | HIV.A5 Create new client record
@description: Calculated age (number of years) of the client based on date of birth
*/
define "Age In Years":
  AgeInYearsAt(start of "Measurement Period")

/*
 * By Age Stratifiers
 * Age (0–4, 5–9, 10–14, 15–19, 20–24, 25–49, 50+ years)
 * 
 */
define "By Age Stratifier 2":
  case 
      when "Age In Years" <= 4 then '0-4'
      when "Age In Years" <= 9 then '5-9'
      when "Age In Years" <= 14 then '10–14'
      when "Age In Years" <= 19 then '15–19'
      when "Age In Years" <= 24 then '20–24'
      when "Age In Years" <= 49 then '25–49'
      when "Age In Years" >= 50 then '50+'
      else null
  end

// Geographic Region
define "By Geographic Region Stratifier":
    First(Patient.address A where A.use in { 'home' }).state

/**
 * HIV Elements
 */

/* General Data Elements */

// From Common

define "Community_testing":
  exists([Observation] O
    with [Encounter] E
      such that O.encounter.references(E) and exists(E.location.physicalType PT where PT ~  Concepts."Community-level testing") 
  where (O.status in { 'final', 'amended' }
  and O.code ~ Concepts."Rapid diagnostic test for HIV - HIV.B.DE82"
  and O.issued after start of "Measurement Period"
  and O.issued before end of "Measurement Period"))

/*@triggeredBy Encounter with location = facility level testing*/
define "Facility_testing":
  exists([Observation] O
    with [Encounter] E
      such that O.encounter.references(E) and exists(E.location.physicalType PT where PT ~  Concepts."Facility-level testing")
  where (O.status in { 'final', 'amended' }
  and O.code ~ Concepts."Rapid diagnostic test for HIV - HIV.B.DE82"
  and O.issued after start of "Measurement Period"
  and O.issued before end of "Measurement Period")
  )

define setting:
  case
    when Community_testing then Concepts."Community-level testing"
    when Facility_testing then Concepts."Facility-level testing"
    else null
  end

define "HIV Status Positive Condition":
  [Condition: Concepts."HIV-positive - HIV.B.DE116"] C
    where C.clinicalStatus ~ ConceptsCustom."active"
      and exists(C.category CC where CC ~ ConceptsCustom."encounter-diagnosis")
    sort by start of onset.toInterval()

define "HIV Status Positive Condition":
  Elements."HIV Status Positive Condition" C
  where C.onset before end of "Measurement Period"

/* End of HIV-inconclusive */

/*
@dataElement: HIV.B.DE115 - HIV status
@activity: HIV.B7 Test for HIV using testing algorithm
@description: HIV status reported after applying the national HIV testing algorithm. No single HIV test can provide an HIV-positive diagnosis.
*/
define "HIV Status Observation":
  [Observation: Concepts."HIV status"] O
    where O.status in { 'final', 'amended', 'corrected' }

define "HIV Status Positive Observation":
"HIV Status Observation" O
    where O.value ~ Concepts."HIV-positive - HIV.B.DE116"
      sort by start of effective.toInterval()

define "HIV Status Positive Observation":
  Elements."HIV Status Positive Observation" O
  where O.issued before end of "Measurement Period"
  or O.effective.toInterval() starts before end of "Measurement Period"

define "Has HIV-positive Status":
  exists "HIV Status Positive Condition"
  or exists "HIV Status Positive Observation"

define "HIV Status Negative Observation":
  "HIV Status Observation" O
    where O.value ~ Concepts."HIV-negative - HIV.B.DE117"
    sort by start of effective.toInterval()

/* End of HIV-positive B.DE116 */

define "HIV Status Negative Observation":
  Elements."HIV Status Negative Observation" O
  where O.issued before end of "Measurement Period"
  or O.effective.toInterval() starts before end of "Measurement Period"

/* End of HIV-negative B.DE113 */

/*
@dataElement: HIV.B.DE115 - HIV status
@activity: HIV.B7 Test for HIV using testing algorithm
@description: HIV status reported after applying the national HIV testing algorithm. No single HIV test can provide an HIV-positive diagnosis.
*/


define "HIV Status Stratifier":
  case 
      when "Has HIV-positive Status" then Concepts."HIV-positive - HIV.B.DE116"
      when not exists("HIV Status Positive Condition") and exists("HIV Status Negative Observation") then  Concepts."HIV-negative - HIV.B.DE117"
      else Concepts."Unknown - HIV.B.DE118"
  end

//provider type not provided?

define "Stratification":
 HIE."By Administrative Gender Stratifier".code 
  + ':' + HIE."By Age Stratifier 2"
+ ':' + HIE."By Geographic Region Stratifier"
 + ':' + HIE."setting".code
+ ':' + HIE."HIV Status Stratifier".code

/* End of STI services */

/*
@dataElement: HIV.PRV.DE7 - VMMC
@activity: HIV.B6 Capture or update client history
@description: Client accessed voluntary medical male circumcision (VMMC) services
*/
// define "VMMC_done":
// [Procedure] P
//   where P.status = 'completed'
//   and P.code ~ Concepts."Voluntary medical male circumcision VMMC"


define "VMMC":
  [Procedure] P
  where P.status = 'completed'
  and P.code ~ Concepts."VMMC procedure"

/* End of STI services */

/*
@dataElement: HIV.PRV.DE7 - VMMC
@activity: HIV.B6 Capture or update client history
@description: Client accessed voluntary medical male circumcision (VMMC) services
*/

define "VMMC":
  exists(Elements."VMMC" V where V.performed.toInterval() during "Measurement Period")

/**
 * Measure Population
 *
 * Definition: Total number of people undergoing VMMC performed according to national standard during the reporting period
 * Calculation: Total number of people undergoing VMMC performed according to national standard during the reporting period
 */
                                                       
define "Measure Population":
  HIE."VMMC"

define function ToString(value AdministrativeGender): value.value

define function ToString(value string): value.value

define function ToString(value AddressUse): value.value

/*
@description: Returns true if the given reference is to the given resource
@comment: Returns true if the `id` element of the given resource exactly equals the tail of the given reference.
NOTE: This function assumes resources from the same source server.
*/
define fluent function references(reference FHIR.Reference, resource FHIR.Resource):
  resource.id = Last(Split(reference.reference, '/'))

define function ToConcept(concept FHIR.CodeableConcept):
    if concept is null then
        null
    else
        System.Concept {
            codes: concept.coding C return ToCode(C),
            display: concept.text.value
        }

define function ToCode(coding FHIR.Coding):
    if coding is null then
        null
    else
        System.Code {
          code: coding.code.value,
          system: coding.system.value,
          version: coding.version.value,
          display: coding.display.value
        }

define function ToString(value ObservationStatus): value.value

define function ToDateTime(value instant): value.value

define function ToDateTime(value dateTime): value.value

define function ToString(value ProcedureStatus): value.value

/**
 * Measure Observation
 * Definition: Total number of people undergoing VMMC performed according to national standard during the reporting period
 * Calculation: Total number of people undergoing VMMC performed according to national standard during the reporting period                                                      
 */     

define function "Measure Observation"(Patient "Patient"):
  1